In recent years a great deal of progress has been made in the application of monoclonal antibodies (mAbs) for the diagnosis of most human cancers, using immunohistochemistry and/or radioimmunoimaging. However, at the present time, there is no specific mAbs available for the early detection of esophageal cancers. The project objective is to develop a panel of specific mAbs to novel cell-surface protein(s), lipid(s) and or cell-surface receptor(s), over expressed on esophageal tumor cells. For this purpose, standard hvbridoma technology will be applied using SP2'O mveloma cells and spleen cells from BA.LB/c mice immunized with human esophageal cells or cell-surface components. Hybridomas producing specific mAbs will be selected and cloned by limiting dilution. The cloned hybridoma(s) producing desirable mAb(s) will be chosen for further analysis. Immunofluorescence assay (IFA) will be applied on live cells to determine surface antigen binding. The chemical nature of the mAb-reactive antigen(s) will be determined by SDS-PAGE, autoradiography and immunoblotting techniques. The protein antigen(s) will be purified and the amino acid sequence will be determined to further characterize the antigen(s). If lipid antigens are recognized by any of the mAbs, the chemical nature of the lipid antigen(s) will be determined by TLC. using chemical and immunological staining procedures. The reactivity of the mAbs with human cancerous and noncancerous esophageal tissues will be examined by immunoflorescence, immunoperoxidase stainings, and autoradiography using purified about I-conjugated rnAb(s), to determine whether the mAb(s) is useful for early detection of human esophageal cancers. Purification and characterization of the antigen molecules will also be attempted. Our major objective is to produce immunological reagents for immunodiagnosis and early detection of different types of esophageal carcinomas and to reduce morbidity and mortality caused by these cancers. The mAbs will be useful in our understanding of histogenesis and differentiation of esophageal carcinomas. Phage display technique will also be attempted as an alternative and/or additional method to generate diagnostic/therapeutic reagents.